Centrifugal casting machine



J.l B. LADD CENTRIFUGAL CASTING MACHINE June l0, 1930.

Filed Jan. 19, 1928 ,2 Sheelzs--SheerI l INVEP'OR Mol.

ATTORNEY- June 10, 1930. 1 B LADD 1,762,177

CENTRIFUGAL CA'ST ING MACHINE Filed Jan. 19, 1928 2 Sheets-Sheet 2 ATTORNE Y Patented June 10, 11930 i UNITED STATES PATENT OFFICE JAMES 1a.Lann, or annmonn,

PENNSYLVANIA, A'SSIGNOR T0 UNITED STATES CAST IBON PIPE & FOUNDBYCOMPANY, F BURLINGTON, NEW JERSEY, A CORPORA- TION 0E NEW JERSEY iCENTRIFUGAL CASTING MACHINE Application mea January 19, 192s. serial110,247,783.

My invention relates to machines of the de Lavaud type for thecentrifugal casting of cast iron pipes. Such machines comprise areciprocating carriage sustaining a Water i box and a rotatable mold, hebody of which is enclosed in the `water box. As heretofore constructedsuch machines have been p'rovided with means for reciprocating thecarriage including generally a hydraulic cylingp' 'ler and piston, thespeed of which is affected by a varying load, and the primev object ofmy invention is to provide as a carriage ac tuating means a constantspeed motor so as to maintain the carriage at any desired speed ofmotion, irrespective of varying resistance. A further object of myinvention is to provide improved mechanism for reciprocating the`carriage comprising a rope connected to actuate the carriage ,in eitherdirection and actuated preferably by an electric motor and to rovide' insuch driving mechanism means on preventing (the carriage from strikingthe abutments which limit its motion with injurious or destructiveforce. lgOther ob'ects which I have in view are to protect t e ropeagainst contact Vwith the metal which sometimes issues from the rear endof the mold and for taking up any slack which may form in the rope insuch a manner that the take up device is securely held in any positionit may assume in taking up slack so that the rope cannot again becomeslack.

The nature of my improvements will be best understood as described inconnection [Si with the drawings which illustrate a portion 'ofa"centrifugal casting machine provided with a reciproca-ting carriageactuated by my improved mechanism in which drawings:

Figure 1 is a plan view of the apparatus I@ with the carriage removed.

Figure 2a side elevation of the apparatus with the carriage shown inplace.

Figure 3 a sectional view on the line 3-3 of Fig. 2, and

il Figure 4 a diagram representing the electric circuits and appliances.for controlling the electric motor.

A, A indicate beams forming part of the framing of the casting machineand support- D. ing tracks A1 A1. B indicates the water box whichconstitutes also the carriage supported on the tracks A1 by means of thewheels indicated at B1'. lB2 indicates the mold supported in the waterbox of the carriage, means for rotatingthe mold not being shown, as theyform no part of the present invention. C is the runner by which molteniron is introduced into the mold; C1 an extension of the runner intowhich metal is poured at the top, for instance, by a ladle D. E and E1are abutment stops to limit the travel of the motor, the abutment Ebeing shown as provided with a hollow portion e to give clearance to theapron indicated at F, which is attached to the rear lower side of thecarriage so as to deflect any metal which may issue from the mold andoep it out of contact with the rope which actuates the mold. G indicatesthe wire rope which is attached to the mold in such a way as to actuateit in either direction. By preference I make the attachment throughsprings which will permit of a slight relative movement between thecarriage vand the mold in either direction. As shown, the connection ismade through splringsl H, H1 surroundingl a rod Gr1 to whic the ends ofthe rope are attached and abutting against a downwardly extending lug B3extending from the bottom` of the carriage and forked to embrace the rodas indicated in'Figs. 2 and 3. The rope is actuated by a winding drum I,from 'which it passes over guide pulleys K, K1 and K2 and also overpulleys K3, K4 and K5, forming part of the take up mechanism to bedescribed. The winding drum 1s attached to the shaft I1 to which is alsoattached a worm wheel I2 actuated by a Worm J secured to a Y shaft J1which is actuated by an electric motor indicated at J 2.

It is necessary for the proper operation of the mold carriage that thereshould be no yield due to slack in the driving rope. therefore providean automatic take up mechanism and to prevent any slackening of theropeunder any conditions I provide the take vup mechanism with a specialdevice which prevents its backward movement. As shown, my take up deviceconsists of a hydraulic cylinder L, having -in it a piston Yll) L1 fromwhich extends a piston rod L2 supporting at its end a take up pulleyindicated at K located between the pulleys K*1 and K4 and to preventrearward motion of the take up ulley I provide a non-return valve M1 1nthe conduit M through which uid under pressure enters the cylinder L.

The stopping and startin of the motor 1n either direction is control edby a master switch which also controls the speed of the motor and toslow up and arrest the motion of the carriage at either end of itstravel so that it will not strike the abutments with injurious `force Iprovide slow down limit switches 23 and stop limit switches 17 which areactuated by the movements of the carriage through some convenient apliance, as, for instance, lu s N and N1, I e electric circuits and appiances are clearly indicated in the diagram, Fig. 4, the parts whereofare indicated as follows: 1 is the motor armature; 2 is the directcurrent power supply; 3 is the shunt field; 4 is the field rheostat; 5is the starting resistance ;v 6 is the slow down and acceleratingcontactor; 7 is a two-pole magnetic contactor and 7A Vbeing the normallyclosed contact of contactor 7; 8 a two-pole magnetic contactor and 8Athe normally closed contact of contactor 8; 9 is a dynamic breakingresistance; 10 an operating coil for the slowdown and acceleratincontactor 6; 11 is the normally closed-in ofig position of the masterswitch; -12 contact of low voltage relay; 13 the operating coil for thelow voltage relay; 14 1s the master switch contacts closed in the firstpouring or return position of master switch. 15 is the operating coilfor the return contactor 8; 17 indicates the stop limit switches and 18master switch contacts closed on the 2nd point pour and return positionsof master switch; 19 is the operatin coil for the high speed contactor20; 21 is t e main line knife switch; 22 is the control circuit knifeswitch;

23 indicates the slow down limit switches;

24 is a drum switch mechanically coupled to the master switch 14. l

In operation contact 11 of master switch 14 is closed only in the offposition of the master switch, therefore when power is applied at 2 theoperating coil of low volta e relay 13 is energized and the contacts 121n closing make operation possible through contacts 18 of master switch.

The carriage is of course at rest at either end of its stroke. Foractuating the motor to move carriage slowly in either direction themaster swltch is thrown vto the first point in either direction, whichstarts the motor to a slow speed, corresponding to the setting of thefield rheostat 4.

When the carriage passes the slow down limit' switch 23l the motor isautomatically slowed down to below normal speed by inserting armatureresistance 5 and applying full voltage to the, motor shunt field 3. Whenthe stop limit switch 17 is reached by the carriage, the motor armature1 is disconnected from the lineand the electrical breaking is obtainedby inserting resistance 9 in parallel with the armature 1, thus brin ingthe motor to a stop.

W ere it is desired to actuate the motor at high speed, the masterswitch is thrown to the second point in either direction, the limitswitches operating in the s'ame way.

The electric motor described is a constant speed motor and apart fromthe other features of my invention I consider the use of such a motor orof any constant speed motor to actuate the carria e as a distinctimprovement in the type o apparatus described. v

Having now described my invention, what I claim as new and desire tosecure by Letters Patent, isz" 1. In a machine for the centrifugalcasting of pipes having a reciprocating mold carrying carriage, meansfor reciprocatin the carriage comprising a rope connected to move thecarriage in opposite directions and means for actuating t an electricmotor. 2. In a machine for the centrifugal casting of pipes having areciprocating mold carrying carriage, means for reciprocatin thecarriage comprising a rope connected to move the carriage in oppositedirections, means for actuating the rope including an electric motor andan apron secured to the rear of the carriage for protecting the ropefrom molten metal escaping from the end of themold. 3. In a machine forthe centrifugal casting onf pipes having a reciprocating mold means forreciprocating e rope including carrying carriage, the carriagecomprising a rope connected to move the carriage in .oppositedirections, means for actuatin the rope including an electricmotor, aneectric circuit system for actuating the motor in either directioncomprising a master switch, slow down limit switches and stop limitswitches and means controlled by the movement of the carriage foractuating successively a slow down and a stop switch as the carriageapproaches the ends of its reciprocatory movement.

4. In a machine for the centrifugal cast- `ing of pipes having areciprocating mold carrying carriage, means for reciprocating thecarriage comprising a rope connected to move the carriage in oppositedirections, means y'for actuating the rope including a constant speedelectric motor, an electric circuit system for actuating the motor ineither direction comprising a master switch, slow down limit switchesand stop limit switches and means controlled by the movement of thecarriage for actuating successively a slow down and a stop switch as thecarriage approaches the ends of its reciprocatory movement. v

5. In a machine for the centrifugal casting of pipes vhaving areciprocating mold carrying carriage, means for reclprocatm the carriagecomprising a rope connecte to move the carriage 1n opposite directions,l

slack in theautomatic means for taking u rope including a stop device orpreventing a backward movement of the take up mechanism and means foractuating t e rope including an electric motor.

JAMES B. LADD.

